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Blender 2.67: Motion Tracker

Dopesheet View

Background color in dopesheet

The Dopesheet view had a minor interface improvement and is now highlighting the background depending on the number of tracks in a frame (r54750). This means that if for a frame (or sequence of frames) there're less than 8 tracks, the background will turn red; if there are from 8 to 16 tracks, the background will be yellow.

This is only a visual feedback, which doesn't mean that the camera motion won't reconstruct with less than 8 tracks. It only means that the user should pay attention to those frames and check if all possible good feature points are tracked there. Remember, if there are no good feature points in the frame and there are less than 16 tracks in the frame, it doesn't mean the solution won't be accurate. Rather, adding more tracks on crappy feature points will reduce the accuracy of solution.

Tripod Solver

Tripod solver was also rewritten from scratch, and also uses Ceres library now (r54932).

Because of using Ceres library and bundle adjustment step tripod solver became much more accurate for calibrated camera shots. For uncalibrated camera shots (when distortion coefficients or focal length are not exactly known), refining of camera intrinsics is now possible.

Please note, that this is special type of camera solver and it behaves different from regular solver. It means using more tracks doesn't imply more accurate solution. Having 5-10 tracks on frame is likely what shall be commonly used for this kind of solver.

Prefetching

In fact, it's not real prefetching in it's movie players understanding. It is an operator which is invoking by P and which fills cache with frames. As many frames as fits into cache are load form the disk.

This allows to fill in the cache as fast as possible when you really need to track something, but this keeps CPU and HDD bandwidth idle if you've got clip editor opened but not actually interacting with it.

2D stabilization was broken for a while, which resulted in nearest interpolation used if there's no rotation, also stable image buffer used to be re-generated on every redraw. This behaves correct now. As an additional stable frame calculation is threaded now (r55901)